It’s unclear if the Pacific Northwest name Tricholoma zelleri is synonymous with the earlier, European T. focale. Compare, e.g., A.E. Bessette, A.R. Bessette, W. Roody, S. Trudell Tricholomas of North America 66 (Univ. of Texas Press 2013) (“generally considered to be a synonym”) with Noah Siegel & Christian Schwarz, 386 (Ten Speed Press 2016) (http://www.redwoodcoastmushrooms.org) ("may turn out to be distinct from the true (European) T. focale, and for this reason some mycologists use the name T. zelleri.